PROCEEDINGS OF THE CHEMICAL DEPARTMENT. 217 



In this case, also, phosphates had been left undissolved, but 

 under the particular circumstances of the case this was not 

 objectionable, as they served to place this and the preceding 

 manure more nearly on a level. 



3d, Sulphate of ammonia. — This was a good sample, but rather 

 moist. It contained 24*43 per cent, of ammonia. 



4th, Glue. — It was well-stoved glue, ground under edgestones, 

 in the same manner as that used in the previous years. It con- 

 tained 13-88 per cent, of nitrogen, equal to 16-85 of ammonia. 



5th, Peruvian guano. — This was a fair average of the imports 

 at the present time, and contained, — ■ 



Water, 14-27 



Organic matter and Ammoniacal Salts, . . . 48 - 98 



Phosphates, 221 5 



Alkaline Salts, 12-45 



Sand, 2-15 



100-00 



Ammonia, 14-82 



Phosphoric Acid in the Alkaline Salts, equal to 4*48 ) 



Phosphate of Lime, ] 2 ' 05 



6 th, Bolivian Guano, of the kind which has been largely im- 

 ported during the last eight or ten years, containing — 



Water, 8-40 



Organic matter and Ammoniacal Salts, . . . 18 - 55 



Phosphates, 61 75 



Alkaline Salts, 5-10 



Sand, 6-20 



100 00 



Ammonia, 0"97 



Phosphoric Acid in the Alkaline Salts, equal to 5-70 ) 



Phosphate of Lime, ] 2 ' b2 



Both these manures were used just as they are in ordinary cases. 

 In fact, it was neither advisable nor possible to start from a 

 given quantity of any of their useful constituents, and it became 

 necessary to fix the amount to be applied per acre as it would be 

 done on the farm. They were, accordingly, employed at the 

 rate of 7 cwt. per acre, which, though a large, is by no means an 

 excessive application, when they are used without farm-yard 

 manure. It is, I believe, quite customary in such cases for the 

 farmer to use as much as 8 cwt. per acre. These quantities 

 yield per acre the following weights of phosphoric acid and 

 ammonia, in lbs. : — 



Total Phosphoric Acid. Ammonia. 



Peruvian Guano, . . . 95*5 . . . 116'3 

 Bolivian Guano, . . . 242-0 . . . 7-1 



It is here particularly to be noted that the quantities of these 



